Crank-shaft bracket for bicycles



(No Model.) i

' R. PERKINS.

GRANK SHAFT BRACKET FOR BIGYGLES, &o.` Nuo. 496,132.

Patented Apr. 25, 1893.

I www5/5.155.154.. .5752? UNITED STATES PATENT OFFICE.

ROBERT PERKINS, OF ROCKAWAY,NEW JERSEY.

ACRANK-SHAFT BRACKET FOR BICYCLES, 86C.

SPECIFICATION forming part of Letters Patent No. 496,132, dated April 25, 1893.

Application filed February '7. 1893. Serial No. 461350. (No model.)

Too/ZZ whom it may concern:

Be it known that I, ROBERT PERKINS, a subject of the Queen of Great Britain, residing at Rockaway7 State of New Jersey, have invented a certain new and usefulImprovement in Crank-Shaft Brackets for Bicycles and other Vehicles; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, forming part of this speciication.

My invention has relation to the frame structure of` bicycles, &c., and consists in the novel construction of a crank shaft bracket or crank hanger hereinafter particularly described.

The object of my invention is to provide a construction of a crank-shaft bracket or crank hanger of great strength and durability which will at the same time be light in weight,easy of adjustment and of assemblement of the parts, and of superior free running qualities. As is well known that portion of the machine to which the crank hanger is applied is subject to severe strain, occasioned principally by the Weight of the rider, the application of the power to the pedals and occasional collision or fall. construction of a substantial, durable machine that the crank hanger and its connecting frame tubes should be constructed as rigidly as possible preventing the connecting frame tubes from being pulled out of the shaft casing, or telescoped into it, and to withstand the various lateral strains to which the machine is liable. Such a construction I accomplish in my invention, as hereinafter described.

In the accompanying drawings, in which similar letters of reference refer to similar parts throughout, Figure l is a perspective View of my improved crank shaft bracket, or crank hanger, showing the connecting parts in broken lines. Fig. 2 is a sectionalview on the line of Fig. 1. Fig. 3 is a sectional view on the line fy-y of Fig. 2.

A is the main cylindrical shaft casing, horizontally disposed, carrying the crank axle, B, in the ball bearing surfaces, such as b, b', provided within said casing, A, at either end, as shown in Fig. 2. The casing or tubing, A,

It is vtherefore requisite in the through the orifice, o, provided in the walls of the tubing, A, and against the interior surface of the walls of the frame tubes a, a,a2, a3; a flange, a4, is also preferably provided upon the lower end of the frame tubes abutting againstthe outer surface of the walls of the main tubing, A, to present a retaining sury face of greater area, though these anges may be dispensed with. The parts as a whole when assembled and adj ustedinto position are then brazed, soldered, or otherwise secured together by any well known means, forming one rigid struct-ure capable of sustaining unusual weight and resisting great strain.

The main barrel of the thimble, c, may be of any desired length, though the proportionate length illustrated in the drawings is preferable. The axle, B, as before stated, is provided longitudinally through the main tubular casing A, in the ball bearings, o, b', carrying the crank arms, d, and the sprocket wheel, e.

The structure described is preferably constructed of steel tubing, though other material may be employed.

My invention has special reference to bicycles, though it may be applied to other vehicle structures.

The main horizontal casing is illustrated in the drawings as having four frame tubings provided thereto. It is clear that other numbers of tubings may be provided without departing from the spirit of my invention.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

l. A crank-shaft bracket having a main horizontally disposed shaft-casing for carrying the crank shaft and its bearings, frame tubes provided upon the outer walls of said main casing having their lower ends abutting against the same, orifices provided in the IOC main casing opposite the respective frame tubes of a diameter equal to the interior-diameter of the frame tube, thimbles provided through the walls of the said main casing and into the interior of said frame tubes having the exterior surface of the walls of the barrel of the thimble snugly fitting andv impinging against the interior surface of the walls of the frame tubes, and outwardly projecting flanges provided on the inner ends of the thimbles impinging against the interior surface of the walls of the main casing, the said parts brazed, or secured together by other like means, fornuin g one rigid Whole substantially as described'.

2. In a crankshaft bracketa main horizontally disposed shaft casing having crankshaft and bearings provided therein, frame tubes provided pon the exterior of the walls of said casing abutting against the sanie, orifices provided sai'd casing registering with the interior bore of the respective frame tubes, thirn bles provided in said fra'lne tubes snugly iinpin ging against the interior walls thereof and protruding through said axle casing, an inner outwardly extending flange provided upon said thi mbles in said axle casing and impinging against the inner walls thereof, the whole brazed or soldered together forming one rigid structure substantially as described.

3. In a crank hangera main axle casing, A, for carrying the axle and its bearings, frame tubes, a, a', a2, a3, having circular outwardly extending flanges, a4, provided upon the lower ends of the same impinging against the outer surface of the-walls of the casing, A, thimbles, c, protruding through said casing, A, in 

